The most vexing thing about the annual flu vaccination is that it’s annual.

You have to get it every year, and many people don’t do so. In fact, the Centers for Disease Control and Prevention recently reported that only 2 out of 5 Americans have received the shot so far this flu season.

Wouldn’t it be easier if a flu shot were a once-in-a-lifetime event, or even once or twice in a decade? Public health officials see that as a potential game-changer.

“If we had an effective universal vaccine, it would take a huge dent out of health-care costs [and] disruption of work, school attendance and social activities,” says William Schaffner, a professor of medicine at Vanderbilt University and medical director of the National Foundation for Infectious Diseases. “It could change the entire way we prevent influenza.”

The idea no longer seems so elusive, says Barney Graham, deputy director of the vaccine research center at the National Institute of Allergy and Infectious Diseases. Modern molecular technology enables scientists “to design things at atomic resolution,” which “really wasn’t possible until the last few years,” says Graham, who is trying to develop what scientists call a universal, or long-lasting, vaccine.